The crew said that the temperatures in the event horizon were "icy".. or "below freezing".. if thats so, why in the beginning AND the middle of the movie do you see a bottle of water floating around and the contents sloshing around? Wouldn't it have already frozen?

Further to my previous comment I was considering mentioning that the coolant from the magnetic core was not frozen as well...but then I realised that this may possibly be because the coolant compound may have a lower freezing temperature than water.
Another slightly funny slip-up I can't be bothered reporting was when Miller & Weir are in the engineering room and Weir crawls into the machine to do some repair. Just before they do that though, they both head over to open the panel, amusingly Miller (Lawrence Fishburne) grabs the wrong panel before realising he should have grabbed the next one over.